Soundlab Audiophile G9-7c: a 30-year odyssey fulfilled

[godofwealth]

In Greek mythology, The Odyssey is a fabulous 24-volume set of poems by Homer that chronicles the voyage home of Odysseus, the King of Ithaca, after the Trojan war. In my case, my 30-year odyssey began in the early 1990s when I acquired my first electrostatic loudspeaker, the Quad ESL-63 US Monitor. I then became aware of the US company Soundlab that made large and imposing electrostatic loudspeakers from an article in Computer Music journal published by MIT Press. In the ensuing decades, the prospect of owning such a large and expensive loudspeaker was impractical. Till now!

I’m pleased to announce that I have now taken possession of one of Soundlab’s largest models, the Audiophile G9-7c. Words are inadequate to describe the quality of this state of the art assault on loudspeakers, except that it reeks of a certain fastidiousness and obsessiveness with perfection that is increasingly rare in our commercial world.

My custom made pair is finished in a handsome dark walnut with a light Opal fabric. These are immense loudspeakers and truly require a long-term ownership to come to terms with their remarkable sound. Accordingly this thread will be updated periodically as I rotate through my various gear to get a better sense of its (lack of) sound. It’s easy enough to summarize their sound in one word: naturality. They just sound entirely at ease playing music with an unforced quality that compares with live music.

Much more to come. A great shout out to Chris and Brett from Soundlab for kindly delivering and installing this magnificent loudspeaker. One pic attached. My ceilings are 10- feet tall.

 

[Ron Resnick]

Wow! Congratulations!

Which amplifier will you be starting with?

 

[cjfrbw]

I never heard a Soundlab that I didn't like. The bigger the panel, the better the experience. Congratulations.

 

[godofwealth]

My original plan was to use my recently acquired ARC 750 SEs, but as it turned out, the G9-7c’s are too large to comfortably fit in the room that the ARC amps are currently in. So, I’m right now running the SL’s with Mola Mola electronics (Makua DAC/phono/preamp with the Kaluga monoblocks). The Kalugas are rated 400 watts, and they’re class D, so their sonic profile is perhaps not ideal for large electrostatics. But they do sound very nice.

I’m listening now to one of my favorite recordings, a 400-year old composition by Italian composer Claudio Monteverdi called Selve Morale et Sprituale recorded by Harmonia Mundi. What stands out is how natural the voices and instruments sound and the lack of any crossover means the full range SLs exhibit a seamlessness across the frequency spectrum. Due to their size they sound remarkably coherent as the climaxes build up on choral passages. In my various Quads, voices begin to distort as the panels begin to reach their limits. Here that’s not an issue as the big Soundlabs can handle 600 watts. They also go very low as I tested with a lovely recording of Durufle’s Mass with a pipe organ. The low frequencies are un-subwoofer like, just cut from the same cloth as the rest of the sonic spectrum.

Looking forward to hearing these with my tube gear (Lampi Pacific, ARC 6SE, ARC 750SEs). But that’s a major rearrangement of my listening rooms that’s a project for another day! .

 

[godofwealth]

A wide-angle pic of the SLs in my listening room. The room is quite large, around 6000 cu ft, and yet the speakers dominate the room. They have a radiating surface of around 3100 inches, and have a 45 degree directivity pattern. The term “loudspeaker” is an unfortunate misnomer here. It’s a strange sensation to hear these as the volume control is raised. They don’t get loud subjectively speaking. As you walk towards them or away from them, the sound remains remarkably stable. It’s an eerie sensation because most loudspeakers get loud as you crank up the volume. These don’t seem to in the same way. There’s a very graceful quality about their sound production that’s due to their large surface area.

 

[godofwealth]

The backplate is itself large, containing 40 pounds of electronics including a large toroidal transformer. Parts quality and the build is extraordinarily compared to the Quads I have owned. The speaker’s sound is customizable with frequency response controls and bias adjustment.

 

[Johan K]

In Greek mythology, The Odyssey is a fabulous 24-volume set of poems by Homer that chronicles the voyage home of Odysseus, the King of Ithaca, after the Trojan war. In my case, my 30-year odyssey began in the early 1990s when I acquired my first electrostatic loudspeaker, the Quad ESL-63 US Monitor. I then became aware of the US company Soundlab that made large and imposing electrostatic loudspeakers from an article in Computer Music journal published by MIT Press. In the ensuing decades, the prospect of owning such a large and expensive loudspeaker was impractical. Till now!

I’m pleased to announce that I have now taken possession of one of Soundlab’s largest models, the Audiophile G9-7c. Words are inadequate to describe the quality of this state of the art assault on loudspeakers, except that it reeks of a certain fastidiousness and obsessiveness with perfection that is increasingly rare in our commercial world.

My custom made pair is finished in a handsome dark walnut with a light Opal fabric. These are immense loudspeakers and truly require a long-term ownership to come to terms with their remarkable sound. Accordingly this thread will be updated periodically as I rotate through my various gear to get a better sense of its (lack of) sound. It’s easy enough to summarize their sound in one word: naturality. They just sound entirely at ease playing music with an unforced quality that compares with live music.

Much more to come. A great shout out to Chris and Brett from Soundlab for kindly delivering and installing this magnificent loudspeaker. One pic attached. My ceilings are 10- feet tall.

View attachment 136833

Congratulations! Looks very impressive! As an MartinLogan owner myself, I really appreciate the sound of electrostatic panels. Have fun!

/ Jk

 

[godofwealth]

The tiny diminutive Mola Mola Kaluga class D mono blocks driving the enormously larger SLs.

 

[Audiohertz2]

What would be different sonically to you between the Mola Mola and your ARC? as you seem to enjoy the sound you have currently..

 

[godofwealth]

I found this website very useful in terms of giving background on SLs, including the sizes of the latest offerings, as well as the wide range of customizable options you get. SL is rare in that they offer each model in a very wide range of wood finishes as well as fabrics. Most other electrostatic loudspeakers (Quads, ML) seem to come in either one color (funeral black for Quads now) or one of a small set of fixed choices. I found this absolutely essential in considering getting a speaker that just dominates even a large listening room.

Sound Lab Electrostats Japan

soundlabelectrostats.com

Their design is intrinsically a line source with no electronic contouring of the sound to mimic a point source, as Quads have done since the ESL-63 model. After owing Quads for 30 years or more, I have found that every 63-based model exhibits a modicum of midrange glare that gets progressively worse as the loudspeaker is driven harder. I think this glare is at least partly due to the miles of wiring in each Quad that is in the inductors that constitute the delay lines. While Peter Walker came up with a technically ingenious solution to keeping the directivity uniform, he was primarily interested in solutions that kept the cost down, and produced a speaker that could fit into small British living rooms. The design principles of the SL models, such as the one I have, are entirely different: they are interested in pushing the boundaries of what is possible and require far greater investments in money, space, and upstream electronics. When Walker designed the 63s, high-resolution digital streaming did not exist, and he personally thought that the BBC FM broadcasts were far better than vinyl replay of his day. He designed very elaborate tone controls in his electronics because of what he perceived as the rather high distortion from vinyl replay in the high treble. The one exception he made was live BBC broadcasts where he recommended disabling the tone controls. Now, we are in a different world entirely where we have access to a very large number of high-resolution recordings with much higher dynamic range. This makes SL speakers much more suitable to the modern era than the vintage 63s (which still sound lovely to my ears, but only at low volumes in smaller rooms).

 

[godofwealth]

What would be different sonically to you between the Mola Mola and your ARC? as you seem to enjoy the sound you have currently..

I have heard the Mola Mola and the ARC on a variety of loudspeakers in. my house (Quads, Harbeth etc.). I think their sonic signatures are worlds apart. The Mola Mola is a nice amplifier, compact, runs relatively cool, and can be easily lifted in one hand! But it's no match for the stupendous sound that comes from the ARC 750SEs that is hard to explain. 18 KT150 tubes with a huge power supply produces a really authoritative sound that wakes up any loudspeaker and even my relatively bass-shy Quads sounded much more impactful. One huge problem in driving electrostatics is that the impedance varies from above 30 ohms in the bass to around 2 ohms in the high treble. They tend to be highly capacitive, and even with Quads, the phase angles can be high. Class D amplifiers tend to be relatively sensitive to the load they are driving. I think the larger tube amplifiers just seem to adjust to the crazy impedance swings in electrostatic loudspeakers better than class D amplifiers in my experience.

 

[unboxed]

Congratulaltions. Your journey will continue. I replaced every component and many cables after acquiring my Sound Labs. They deserve the best.

 

[Bso]

Congratulaltions. Your journey will continue. I replaced every component and many cables after acquiring my Sound Labs. They deserve the best.

Consider trying a pair of Benchmark ABH2s bridged in mono using their SpeakOn cables since they have ample voltage and current to drive the impedance of the SLs. They have the uncanny ability to totally disappear if fed by the right low noise source which makes the SLs disappear even more. One can walk around and inside the image.

Of course, this implies that one uses true balanced ancillaries if possible.

With the Benchmarks and the SLs I find, with less than ideal upstream electronics, one does not hear the contributed noise per se; rather it is the timbre, resolution and imaging that is compromised.

 

[AudioLibertarian]

Consider trying a pair of Benchmark ABH2s bridged in mono using their SpeakOn cables since they have ample voltage and current to drive the impedance of the SLs. They have the uncanny ability to totally disappear if fed by the right low noise source which makes the SLs disappear even more. One can walk around and inside the image.

Of course, this implies that one uses true balanced ancillaries if possible.

With the Benchmarks and the SLs I find, with less than ideal upstream electronics, one does not hear the contributed noise per se; rather it is the timbre, resolution and imaging that is compromised.

The aforementioned Behchmark amps, especially in bridged in mono are decidedly mediocre, and are NOWHERE near the league of the Sound Lab speakers. Yes , they have received some good reviews, by folks who have a very poor frame of reference, but for the Sound Labs top of the line speakers?!! Pulezzee...

 

[Audiohertz2]

I have heard the Mola Mola and the ARC on a variety of loudspeakers in. my house (Quads, Harbeth etc.). I think their sonic signatures are worlds apart. The Mola Mola is a nice amplifier, compact, runs relatively cool, and can be easily lifted in one hand! But it's no match for the stupendous sound that comes from the ARC 750SEs that is hard to explain. 18 KT150 tubes with a huge power supply produces a really authoritative sound that wakes up any loudspeaker and even my relatively bass-shy Quads sounded much more impactful. One huge problem in driving electrostatics is that the impedance varies from above 30 ohms in the bass to around 2 ohms in the high treble. They tend to be highly capacitive, and even with Quads, the phase angles can be high. Class D amplifiers tend to be relatively sensitive to the load they are driving. I think the larger tube amplifiers just seem to adjust to the crazy impedance swings in electrostatic loudspeakers better than class D amplifiers in my experience.

It’s why i asked , cant handle the poor timbre of Class D when tried ..

 

[cjfrbw]

I tried a few class D types to have a 'cool running' system for the summer. They have come a long way from the dusty, uninvolving class D that I remember from the day and at shows. I got the cheapest class D GanFet type, the mini Gan 5, used, and I am shocked at how good it sounds. Big soundstage, incisive, pleasing to listen to, highly detailed, decent depth, very 'fast' sounding. It has nominal power, too for the adamant power hogs.

The mini Gan 5 was roundly trashed by Amir at ASR due to measuring glitches, and the objectivist hyenas kind of finished the job because nobody there is ALLOWED to discuss subjective sound quality, but this little amp is the real deal in sound quality. It has the dynamic open-ness reminiscent of single ended tubes in the upper midrange, and a sound stage without compression or barrel distortion, although it does have its own sound and is not strictly comparable.

I think that single ended, fleas, class A Mosfet still are competitive because the mini Gan 5 is kind a 'literal' amp, and other types still have some liquidity and charm, and transmitting tube types have that organic wholeism, but I do think the little Gan thingie puts just about any class AB BJT bipolar type I have ever heard to bed.

 

[godofwealth]

Dr. Roger West, who founded Soundlab, received his PhD in psychoacoustics from Stanford, a topic undoubtedly befitting a future designer of loudspeakers. There’s a nice interview with him at this link:

Interview with Roger West of Sound Lab

I have always been a huge fan of Roger West. owner and designer of Sound Lab electrostatic panel speakers. I make no apologies for my love of his giant Ultimate I full-range electrostatic speakers. I have listened to thousands of speakers over my 52 years in audio, from the very cheapest to...

www.dagogo.com

My manual ends with a short terse statement of the type you find in scientific journals, but usually not in audio magazine advertisements.

“The Audiophile 945 incorporates Sound Lab’s distributed resonance principle, which is protected by US Patent No. 5,054,,081”.

This very understated remark may in actuality be one of SL’s true breakthroughs. In my experience full-range electrostatics have a pronounced bass “drumhead” resonance effect. My Quad 2905 exhibits this effect quite noticeably both audibly and from measurements I’ve seen reported in various reviews. Stereophile reported the following measurement of the Quad 2912, a revised version of my 2905. Notice the pronounced bass peak at 50 Hz. I briefly owned a full-range Martin Logan CLS that exhibited an even worse drumhead bass resonance.

Here’s the kicker. My initial impression is that my SL does not audibly exhibit any such resonance. It has certainly deep bass to reproduce pipe organ notes in the mid-20 Hz range. But there’s no mid-bass hump that I previously observed with my 2905s or CLS’es. And the above US patent may be why SL has overcome this problem, making their large panel speakers sound more accurate through the bass.

Figure: Quad 2912 measurements reported in Stereophile.

 

[AudioLibertarian]

Dr. Roger West, who founded Soundlab, received his PhD in psychoacoustics from Stanford, a topic undoubtedly befitting a future designer of loudspeakers. There’s a nice interview with him at this link:

Interview with Roger West of Sound Lab

I have always been a huge fan of Roger West. owner and designer of Sound Lab electrostatic panel speakers. I make no apologies for my love of his giant Ultimate I full-range electrostatic speakers. I have listened to thousands of speakers over my 52 years in audio, from the very cheapest to...

www.dagogo.com

My manual ends with a short terse statement of the type you find in scientific journals, but usually not in audio magazine advertisements.

“The Audiophile 945 incorporates Sound Lab’s distributed resonance principle, which is protected by US Patent No. 5,054,,081”.

This very understated remark may in actuality be one of SL’s true breakthroughs. In my experience full-range electrostatics have a pronounced bass “drumhead” resonance effect. My Quad 2905 exhibits this effect quite noticeably both audibly and from measurements I’ve seen reported in various reviews. Stereophile reported the following measurement of the Quad 2912, a revised version of my 2905. Notice the pronounced bass peak at 50 Hz. I briefly owned a full-range Martin Logan CLS that exhibited an even worse drumhead bass resonance.

Here’s the kicker. My initial impression is that my SL does not audibly exhibit any such resonance. It has certainly deep bass to reproduce pipe organ notes in the mid-20 Hz range. But there’s no mid-bass hump that I previously observed with my 2905s or CLS’es. And the above US patent may be why SL has overcome this problem, making their large panel speakers sound more accurate through the bass.

Figure: Quad 2912 measurements reported in Stereophile.

View attachment 136882

How is the soundstage outside of the sweet spot with these?

 

[godofwealth]

That’s a really interesting question. I’ve found that electrostatics have an interesting property that the sound doesn’t change a lot when you walk towards or away from them. My SLs have this quality in spades. There’s no audible drop out when you stand up or sit down. My La Scala horns sound great when you sit in the middle on a low sofa. When you get up the soundstage collapses. Here, not only does this not happen, it lets you walk around and if your eyes are closed, you can’t really tell that much has changed. Now unavoidably the position of instruments will change, which is a function of our binaural hearing mechanism. An instrument recorded in dead center will shift left or right as your listening position changes. But its sound should not change much.

I’m listening off center to a lovely DSD recording of Vivaldi’s mandolin concertos by the Katona brothers on Channel Classics. Sounds wonderful sitting in dead center or off to one side, modulo instrument location changes.

 

[godofwealth]

Close up pic of the left loudspeaker attached below. This model is called 7c because it is actually made up of 7 vertical strips that are placed in this curved wooden frame. One reason for the wide sweet spot is the 45 degree constant directivity.

It’s really expensive to make a wood frame out of hardwood that bends in the right way, one reason these speakers have to be custom ordered and it takes many weeks to make one. Patience is a virtue here. If you are listening to this speaker everyday for years to come, it’s important they look nice. No getting away from their size however.

Quad’s Peter Walker once famously said that if you like the sound of a grand piano and can afford to get one, you’ll find a way to make room for it in your living room. Amen to that. These Soundlab’s can justifiably be called the Steinway of loudspeakers as they not only sound lovely, they look like it too (keeping in mind beauty is a subjective notion!).